Various types of memory devices store data in two-dimensional or three-dimensional arrays of memory cells. To store data, a controllable physical characteristic of a cell may be changed to represent a particular state. For example, a cell may be capable of storing data based on altering a stored charge within a range of charges, altering a resistance within a range of resistances, or the like. Threshold values for the controllable physical characteristic may divide the range of possible values into different states, where each state may be associated with a data value. However, the controllable physical characteristic for the cells may drift past threshold values, causing errors. For example, drift may occur over time, causing data retention errors, or may occur due to disturbances from other memory operations. Drift may also occur due to temperature or other factors.